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                    updateSuspenseComponent
            
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                    updatePortalComponent
            
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                                <h1 id="&#x4E8B;&#x4EF6;&#x7ED1;&#x5B9A;">&#x4E8B;&#x4EF6;&#x7ED1;&#x5B9A;</h1><p>&#x4E8B;&#x4EF6;&#x7ED1;&#x5B9A;&#x4E3B;&#x8981;&#x662F;&#x5728;&#x521D;&#x59CB;&#x5316; DOM &#x7684;&#x4E8B;&#x4EF6;&#xFF0C;&#x5F53;&#x7136;&#x5728; DOM &#x66F4;&#x65B0;&#x8FC7;&#x7A0B;&#x4E2D;&#x4E5F;&#x4F1A;&#x51FA;&#x73B0;&#xFF0C;&#x4E0D;&#x8FC7;&#x8F83;&#x5C11;&#xFF0C;&#x6240;&#x4EE5;&#x6211;&#x4EEC;&#x5C31;&#x4ECE;&#x521D;&#x59CB;&#x5316; DOM &#x7684;&#x65F6;&#x5019;&#x5165;&#x624B;&#x6765;&#x8BB2;&#x3002;&#x5728;&#x521D;&#x59CB;&#x5316;&#x7684;&#x65F6;&#x5019;&#x6211;&#x4EEC;&#x4F1A;&#x8C03;&#x7528;&#x4E00;&#x4E2A;&#x65B9;&#x6CD5;&#x53EB;&#x505A;<code>setInitialProperties</code>&#xFF0C;&#x8FD9;&#x91CC;&#x4E00;&#x5F00;&#x59CB;&#x5C31;&#x5BF9;&#x4E00;&#x4E9B;&#x7C7B;&#x578B;&#x7684;&#x8282;&#x70B9;&#x6267;&#x884C;&#x4E86;&#x4E00;&#x4E9B;&#x4E8B;&#x4EF6;&#x7ED1;&#x5B9A;&#xFF1A;</p><pre><code class="lang-js"><span class="hljs-keyword">switch</span> (tag) {
  <span class="hljs-keyword">case</span> <span class="hljs-string">&apos;iframe&apos;</span>:
  <span class="hljs-keyword">case</span> <span class="hljs-string">&apos;object&apos;</span>:
    trapBubbledEvent(TOP_LOAD, domElement);
    props = rawProps;
    <span class="hljs-keyword">break</span>;
  <span class="hljs-keyword">case</span> <span class="hljs-string">&apos;video&apos;</span>:
  <span class="hljs-keyword">case</span> <span class="hljs-string">&apos;audio&apos;</span>:
    <span class="hljs-comment">// Create listener for each media event</span>
    <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; mediaEventTypes.length; i++) {
      trapBubbledEvent(mediaEventTypes[i], domElement);
    }
    props = rawProps;
    <span class="hljs-keyword">break</span>;
<span class="hljs-comment">// ... others</span></code></pre>
<p>&#x8FD9;&#x91CC;&#x8C03;&#x7528;&#x7684;&#x65B9;&#x6CD5;&#x662F;<code>trapBubbledEvent</code></p><p>&#x800C;&#x540E;&#x9762;&#x8C03;&#x7528;&#x4E86;&#x65B9;&#x6CD5;<code>setInitialDOMProperties</code>&#x6765;&#x771F;&#x6B63;&#x5F97;&#x521D;&#x59CB;&#x5316; DOM &#x5C5E;&#x6027;</p><pre><code class="lang-js">} <span class="hljs-keyword">else</span> <span class="hljs-keyword">if</span> (registrationNameModules.hasOwnProperty(propKey)) {
  <span class="hljs-keyword">if</span> (nextProp != <span class="hljs-literal">null</span>) {
    <span class="hljs-keyword">if</span> (__DEV__ &amp;&amp; <span class="hljs-keyword">typeof</span> nextProp !== <span class="hljs-string">&apos;function&apos;</span>) {
      warnForInvalidEventListener(propKey, nextProp);
    }
    ensureListeningTo(rootContainerElement, propKey);
  }
}</code></pre>
<p>&#x8FD9;&#x91CC;&#x5224;&#x65AD;&#x4E86;&#x67D0;&#x4E2A;<code>propKey</code>&#x662F;&#x5426;&#x5728;<code>registrationNameModules</code>&#x4E2D;&#xFF0C;&#x800C;<code>registrationNameModules</code>&#x662F;&#x6211;&#x4EEC;&#x5728;&#x521D;&#x59CB;&#x5316;&#x4E8B;&#x4EF6;&#x7CFB;&#x7EDF;&#x4E2D;&#x6CE8;&#x518C;&#x7684;&#x4E8B;&#x4EF6;&#x540D;&#x5BF9;&#x5E94;&#x7684;&#x6A21;&#x5757;&#x7684;&#x5BF9;&#x8C61;&#xFF0C;&#x8FD9;&#x5C31;&#x8054;&#x7CFB;&#x8D77;&#x6765;&#x4E86;&#x3002;</p><p>&#x8FD9;&#x91CC;&#x8C03;&#x7528;&#x4E86;<code>ensureListeningTo</code>&#xFF0C;&#x6211;&#x4EEC;&#x6765;&#x770B;&#x4E00;&#x4E0B;&#x4EE3;&#x7801;&#xFF1A;</p><pre><code class="lang-js"><span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">ensureListeningTo</span>(<span class="hljs-params">rootContainerElement, registrationName</span>) </span>{
  <span class="hljs-keyword">const</span> isDocumentOrFragment =
    rootContainerElement.nodeType === DOCUMENT_NODE ||
    rootContainerElement.nodeType === DOCUMENT_FRAGMENT_NODE
  <span class="hljs-keyword">const</span> doc = isDocumentOrFragment
    ? rootContainerElement
    : rootContainerElement.ownerDocument
  listenTo(registrationName, doc)
}</code></pre>
<p><code>rootContainerElement</code>&#x662F; React &#x5E94;&#x7528;&#x7684;&#x6302;&#x8F7D;&#x70B9;&#xFF0C;&#x6216;&#x8005;&#x662F;<code>HostPortal</code>&#x7684;<code>container</code>&#xFF0C;&#x6240;&#x4EE5;&#x8FD9;&#x4E9B;&#x4E8B;&#x4EF6;&#x5176;&#x5B9E;&#x90FD;&#x662F;&#x901A;&#x8FC7;&#x4E8B;&#x4EF6;&#x4EE3;&#x7406;&#x6765;&#x5B9E;&#x73B0;&#x7684;&#x3002;&#x6211;&#x4EEC;&#x7EE7;&#x7EED;&#x770B;<code>listenTo</code>&#x7684;&#x4EE3;&#x7801;&#xFF0C;&#x4ED6;&#x6765;&#x81EA;<code>ReactBrowserEventEmitter.js</code></p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">listenTo</span>(<span class="hljs-params">
  registrationName: string,
  mountAt: Document | Element,
</span>) </span>{
  <span class="hljs-keyword">const</span> isListening = getListeningForDocument(mountAt)
  <span class="hljs-keyword">const</span> dependencies = registrationNameDependencies[registrationName]

  <span class="hljs-keyword">for</span> (<span class="hljs-keyword">let</span> i = <span class="hljs-number">0</span>; i &lt; dependencies.length; i++) {
    <span class="hljs-keyword">const</span> dependency = dependencies[i]
    <span class="hljs-keyword">if</span> (!(isListening.hasOwnProperty(dependency) &amp;&amp; isListening[dependency])) {
      <span class="hljs-keyword">switch</span> (dependency) {
        <span class="hljs-keyword">case</span> TOP_SCROLL:
          trapCapturedEvent(TOP_SCROLL, mountAt)
          <span class="hljs-keyword">break</span>
        <span class="hljs-keyword">case</span> TOP_FOCUS:
        <span class="hljs-keyword">case</span> TOP_BLUR:
          trapCapturedEvent(TOP_FOCUS, mountAt)
          trapCapturedEvent(TOP_BLUR, mountAt)
          <span class="hljs-comment">// We set the flag for a single dependency later in this function,</span>
          <span class="hljs-comment">// but this ensures we mark both as attached rather than just one.</span>
          isListening[TOP_BLUR] = <span class="hljs-literal">true</span>
          isListening[TOP_FOCUS] = <span class="hljs-literal">true</span>
          <span class="hljs-keyword">break</span>
        <span class="hljs-keyword">case</span> TOP_CANCEL:
        <span class="hljs-keyword">case</span> TOP_CLOSE:
          <span class="hljs-keyword">if</span> (isEventSupported(getRawEventName(dependency))) {
            trapCapturedEvent(dependency, mountAt)
          }
          <span class="hljs-keyword">break</span>
        <span class="hljs-keyword">case</span> TOP_INVALID:
        <span class="hljs-keyword">case</span> TOP_SUBMIT:
        <span class="hljs-keyword">case</span> TOP_RESET:
          <span class="hljs-comment">// We listen to them on the target DOM elements.</span>
          <span class="hljs-comment">// Some of them bubble so we don&apos;t want them to fire twice.</span>
          <span class="hljs-keyword">break</span>
        <span class="hljs-keyword">default</span>:
          <span class="hljs-comment">// By default, listen on the top level to all non-media events.</span>
          <span class="hljs-comment">// Media events don&apos;t bubble so adding the listener wouldn&apos;t do anything.</span>
          <span class="hljs-keyword">const</span> isMediaEvent = mediaEventTypes.indexOf(dependency) !== <span class="hljs-number">-1</span>
          <span class="hljs-keyword">if</span> (!isMediaEvent) {
            trapBubbledEvent(dependency, mountAt)
          }
          <span class="hljs-keyword">break</span>
      }
      isListening[dependency] = <span class="hljs-literal">true</span>
    }
  }
}</code></pre>
<p>&#x53EF;&#x4EE5;&#x770B;&#x5230;&#x9664;&#x4E86;&#x4E00;&#x4E9B;&#x7279;&#x5B9A;&#x7684;&#x4E8B;&#x4EF6;&#x8C03;&#x7528;<code>trapCapturedEvent</code>&#x4E4B;&#x5916;&#xFF0C;&#x5176;&#x4ED6;&#x90FD;&#x7ED1;&#x5B9A;<code>trapBubbledEvent</code>&#xFF0C;&#x9700;&#x8981;&#x6CE8;&#x610F;&#x7684;&#x662F;&#xFF0C;&#x7ED1;&#x5B9A;&#x7684;&#x65F6;&#x5019;&#x6211;&#x4EEC;&#x9700;&#x8981;&#x83B7;&#x53D6;&#x67D0;&#x4E2A;&#x4E8B;&#x4EF6;&#x7684;<code>dependencies</code>&#xFF0C;&#x6765;&#x81EA;<code>registrationNameDependencies</code>&#x3002;&#x5176;&#x5B9E;&#x770B;&#x8FD9;&#x4E24;&#x4E2A;&#x65B9;&#x6CD5;&#x7684;&#x540D;&#x5B57;&#x5C31;&#x53EF;&#x4EE5;&#x77E5;&#x9053;&#xFF0C;&#x4ED6;&#x4EEC;&#x5206;&#x522B;&#x76D1;&#x542C;&#x7684;&#x662F;&#x6355;&#x83B7;&#x548C;&#x5192;&#x6CE1;&#x9636;&#x6BB5;&#x3002;&#x63A5;&#x4E0B;&#x53BB;&#x6211;&#x4EEC;&#x5C31;&#x6765;&#x770B;&#x770B;&#x8FD9;&#x4E24;&#x4E2A;&#x65B9;&#x6CD5;&#x505A;&#x4E86;&#x4EC0;&#x4E48;&#x3002;</p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">trapBubbledEvent</span>(<span class="hljs-params">
  topLevelType: DOMTopLevelEventType,
  element: Document | Element,
</span>) </span>{
  <span class="hljs-keyword">if</span> (!element) {
    <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>
  }
  <span class="hljs-keyword">const</span> dispatch = isInteractiveTopLevelEventType(topLevelType)
    ? dispatchInteractiveEvent
    : dispatchEvent

  addEventBubbleListener(
    element,
    getRawEventName(topLevelType),
    <span class="hljs-comment">// Check if interactive and wrap in interactiveUpdates</span>
    dispatch.bind(<span class="hljs-literal">null</span>, topLevelType),
  )
}

<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">trapCapturedEvent</span>(<span class="hljs-params">
  topLevelType: DOMTopLevelEventType,
  element: Document | Element,
</span>) </span>{
  <span class="hljs-keyword">if</span> (!element) {
    <span class="hljs-keyword">return</span> <span class="hljs-literal">null</span>
  }
  <span class="hljs-keyword">const</span> dispatch = isInteractiveTopLevelEventType(topLevelType)
    ? dispatchInteractiveEvent
    : dispatchEvent

  addEventCaptureListener(
    element,
    getRawEventName(topLevelType),
    <span class="hljs-comment">// Check if interactive and wrap in interactiveUpdates</span>
    dispatch.bind(<span class="hljs-literal">null</span>, topLevelType),
  )
}</code></pre>
<p><code>dispatchInteractiveEvent</code>&#x548C;<code>dispatchEvent</code>&#x5206;&#x522B;&#x5BF9;&#x5E94;&#x4E0D;&#x540C;&#x4F18;&#x5148;&#x7EA7;&#x7684;&#x4E8B;&#x4EF6;&#xFF0C;&#x524D;&#x8005;&#x4F18;&#x5148;&#x7EA7;&#x8F83;&#x9AD8;&#xFF0C;&#x5982;&#x679C;&#x5904;&#x4E8E;<code>ConcurrentMode</code>&#x4EA7;&#x751F;&#x7684;<code>expirationTime</code>&#x4F1A;&#x8F83;&#x5C0F;&#x3002;&#x8FD9;&#x4E24;&#x4E2A;&#x65B9;&#x6CD5;&#x6211;&#x4EEC;&#x5230;&#x8BB2;&#x89E3;<a href="event-dispatch.html">&#x4E8B;&#x4EF6;&#x89E6;&#x53D1;&#x8FC7;&#x7A0B;</a>&#x4E2D;&#x53BB;&#x8BB2;&#x89E3;&#x3002;</p><p>&#x800C;<code>addEventBubbleListener</code>&#x548C;<code>addEventCaptureListener</code>&#x8FD9;&#x4E24;&#x4E2A;&#x65B9;&#x6CD5;&#x5C31;&#x5F88;&#x7B80;&#x5355;&#x4E86;&#x3002;</p><pre><code class="lang-js"><span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">addEventBubbleListener</span>(<span class="hljs-params">
  element: Document | Element,
  eventType: string,
  listener: Function,
</span>): <span class="hljs-title">void</span> </span>{
  element.addEventListener(eventType, listener, <span class="hljs-literal">false</span>)
}

<span class="hljs-keyword">export</span> <span class="hljs-function"><span class="hljs-keyword">function</span> <span class="hljs-title">addEventCaptureListener</span>(<span class="hljs-params">
  element: Document | Element,
  eventType: string,
  listener: Function,
</span>): <span class="hljs-title">void</span> </span>{
  element.addEventListener(eventType, listener, <span class="hljs-literal">true</span>)
}</code></pre>
<p>&#x5230;&#x8FD9;&#x91CC;&#x6211;&#x4EEC;&#x5C31;&#x628A;&#x4E8B;&#x4EF6;&#x901A;&#x8FC7;&#x4E8B;&#x4EF6;&#x4EE3;&#x7406;&#x7684;&#x65B9;&#x5F0F;&#x7ED1;&#x5B9A;&#x5230;&#x4E86;<code>container</code>&#x5BF9;&#x8C61;&#x4E0A;&#x3002;&#x5F53;&#x7136;&#x5BF9;&#x4E8E;&#x7279;&#x6B8A;&#x7684;&#x8282;&#x70B9;&#x7684;&#x4E0D;&#x4F1A;&#x5192;&#x6CE1;&#x7684;&#x4E8B;&#x4EF6;&#xFF0C;&#x5728;<code>setInitialProperties</code>&#x4E2D;&#x5DF2;&#x7ECF;&#x4E8B;&#x5148;&#x76F4;&#x63A5;&#x7ED1;&#x5B9A;&#x5230;&#x8282;&#x70B9;&#x4E0A;&#x4E86;&#x3002;</p>
                                
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